unplugged-system/external/ltp/testcases/kernel/mem/hugetlb/hugemmap/hugemmap21.c

119 lines
2.6 KiB
C

// SPDX-License-Identifier: LGPL-2.1-or-later
/*
* Copyright (C) 2005-2006 IBM Corporation.
* Author: David Gibson & Adam Litke
*/
/*\
* [Description]
*
* Tests copy-on-write semantics of large pages where a number of threads
* map the same file with the MAP_PRIVATE flag. The threads then write
* into their copy of the mapping and recheck the contents to ensure they
* were not corrupted by the other threads.
*/
#include "hugetlb.h"
#define THREADS 5
#define NR_HUGEPAGES 6
#define MNTPOINT "hugetlbfs/"
static int fd = -1;
static long hpage_size;
static void do_work(int thread, size_t size, int fd)
{
char *addr;
size_t i;
char pattern = thread+65;
addr = SAFE_MMAP(NULL, size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0);
tst_res(TINFO, "Thread %d (pid %d): Mapped at address %p",
thread, getpid(), addr);
for (i = 0; i < size; i++)
memcpy((char *)addr+i, &pattern, 1);
if (msync(addr, size, MS_SYNC))
tst_brk(TBROK | TERRNO, "Thread %d (pid %d): msync() failed",
thread, getpid());
for (i = 0; i < size; i++) {
if (addr[i] != pattern) {
tst_res(TFAIL, "thread %d (pid: %d): Corruption at %p; "
"Got %c, Expected %c", thread, getpid(),
&addr[i], addr[i], pattern);
goto cleanup;
}
}
tst_res(TINFO, "Thread %d (pid %d): Pattern verified",
thread, getpid());
cleanup:
SAFE_MUNMAP(addr, size);
exit(0);
}
static void run_test(void)
{
int i, pid;
char *addr;
size_t size, itr;
pid_t *wait_list;
wait_list = SAFE_MALLOC(THREADS * sizeof(pid_t));
size = (NR_HUGEPAGES / (THREADS+1)) * hpage_size;
/*
* First, mmap the file with MAP_SHARED and fill with data
* If this is not done, then the fault handler will not be
* called in the kernel since private mappings will be
* created for the children at prefault time.
*/
addr = SAFE_MMAP(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
for (itr = 0; itr < size; itr += 8)
memcpy(addr+itr, "deadbeef", 8);
for (i = 0; i < THREADS; i++) {
pid = SAFE_FORK();
if (pid == 0)
do_work(i, size, fd);
wait_list[i] = pid;
}
tst_reap_children();
SAFE_MUNMAP(addr, size);
free(wait_list);
tst_res(TPASS, "mmap COW working as expected.");
}
static void setup(void)
{
hpage_size = tst_get_hugepage_size();
fd = tst_creat_unlinked(MNTPOINT, 0);
}
static void cleanup(void)
{
if (fd >= 1)
SAFE_CLOSE(fd);
}
static struct tst_test test = {
.needs_root = 1,
.mntpoint = MNTPOINT,
.needs_hugetlbfs = 1,
.needs_tmpdir = 1,
.forks_child = 1,
.setup = setup,
.cleanup = cleanup,
.test_all = run_test,
.hugepages = {NR_HUGEPAGES, TST_NEEDS},
};